Features: 1.Function: Dual battery selector switch can switch isolated battery packs to all loads or combine battery packs to all loads, make before break contact design allows switching without interrupting power. 2.Current: The 300A continuous rating is safe for installation on gasoline powered boats and the 400A intermittent rating is the maximum amount of current that can be loaded for a specified minimum period of time. 3.For Use with 2 Batteries: Isolator switch allows selection between batteries for starting and charging or operation of both in parallel. This switch can be used with 6?32V. 4.Universal Application: Dual battery disconnect switch is universal, can be widely used for marine, boat, RV, big truck, modified car. 5.15mm Studs: Nickel plated copper studs for maximum conductivity and rust resistance, studs can accept M8 ring terminals, 15mm stud length accepts multiple cable terminals. Specification: Item Type: Battery Selector Switch Material: Nickel plated, copper Switch Position: 4 (OFF-1-BOTH(1+2)-2) Battery Combo: Yes Working Voltage: 6-32V DC Continuous Rating: 300A Instantaneous Current at Startup: 400A Number of Binding Posts: 3 Terminal Size: M8 Terminal Length: Approx. 15mm/0.59in Function: Make before break contact design allows switching between battery packs without interrupting power Application: Suitable for Marine, Boat, RV, big truck, modified car